So my head gaskets blown

[red-dead15]

from the title you probably know what this is about, my t4r blew a head gasket, i am in the process of dismantling the head, and i am at the point of getting the engine wire protector and other wires out of the way, but to me its looks like the wiring has been redone, or a least tampered with, you can tell me what you think from the photos (although it may be hard to tell). Another reason for me thinking that it has been redone is because my service manuel tells me where to disconnect the wires but the connections are not there making me have to follow the wire all the way to the end of it, with one of the wires that branches off goes all the way to the center diff before i can disconnect it (last 2 pictures, after last picture it just continues to center diff and splits to 4 connectors) and would also involve me cutting and detaching many points where it is attached to the vehicle, this just doesn't seem correct to me, can anybody tell me there experience with this, it would be a great help.

i do have a remote starter with this vehicle, but that should not conflict with any of these wires.

 

[Clownmeat]

That left side has been messed with. The injector wiring is "funny". Shouldn't have to ever cut anything. Maybe rats got to it at one time or something and they repaired it.

 

[Stick Figure]

Only thing I notice out of place is the hard plastic on the injector loom is broken and has been replaced with some heat reflective stuff. As far as the same harness running all the way to the center diff, I've never been that far into my 4runners wiring, but it wouldn't surprise me. Most Toyota's have a full engine / trans harness that don't disconnect in between. Just be glad it isn't a Mitsu, those engine harnesses ran all the way to the fuel pump.

 

[1985taylor1925]

How could you tell your head gasket was blown?

 

[BrianSD_42]

it could be a cracked head. what CYL was throwing codes?

I suffered a cracked head, failure in CYL #3. You won't know if it is the head gasket or the head itself until you pull it all apart.

 

[Diagram14]

Your wiring looks good. Stick Figure is right about the heat reflector wrap, your previous owner was just caring for the loss of the plastic shroud. Which you'll find out during this project is very brittle and will break even further. The wiring harness does go all the was down to the transmission/transfer case but when you get everything disconnected off the engine it can be tied out of the way very easily. There are some photos here you can see how it just folds out.

 

[red-dead15]

How could you tell your head gasket was blown?

I am not 100% sure it is that, but all signs point to it, white smoke out of exhaust, loss of compression, ect.

Ill know for sure once it is taken apart.

 

[LittleCaesar]

Did you do a leak down test on it to pinpoint the exact cylinder it was leaking from?

 

[red-dead15]

Did you do a leak down test on it to pinpoint the exact cylinder it was leaking from?

No, i figure if i am taking it apart already i am going to redue all gaskets, belts, water pump, and anything else i think need a redue so i am not going to go to the trouble of finding out which cylinder or cylinders are bad.

 

[scottyb]

If you don't have any electrical problems, I wouldn't worry about you wiring. If it was done incorrectly, I'm sure there would be noticeable problems. Also, the plastic wire covers tends to break every time you touch them, so I bet the previous owner just threw away the covers after they shattered and put his own heat wrap on.

When my head gasket failed/heads cracked, air was getting into the coolant (and vice versa) and air was bubbling into the overflow reservoir. You could take a look to see if you have any bubbling.

 

[red-dead15]

So it defiantly was my LH #6 cylinder area that blew and parts of RH gasket were warped so the job was needed. here is what i saw when i took cylinder head off.

 

[Singtoe]

That picture doesn't show anything. It could have filled up with antifreeze when removing the head.

I would have done a compression check first, just to find our what cylinder was the suspect.

We need to see pictures of your head gasket and the each head to see which one was giving the problem.

 

[Baja Runner]

Did you drain your coolant before pulling the heads? If not, that is probably just the coolant coming from the water jackets of the head.

 

[DC runner]

I don't know. That cylinder and piston head looks "cleaner" which you would see with the steam forced out...

 

[jirehn]

What are the effects if the gasket is blown?

 

[maclean216]

How many miles are on your water pump?

 

[DC runner]

What are the effects if the gasket is blown?

Several. White Smoke - The steam being forced out in the combustion cycle. Loss of power. Noticing a large coolant loss and not seeing a puddle under your car. A rough idle.

 

[BrianSD_42]

a crack in the head can be extremely small. you will want to clean and inspect the head paying very close attn to detail.

singtoe has a good point.

 

[Alabamaguy]

Get it magnafluxed and checked to make sure the mating surface is still flat. Cheap insurance.

 

[Diagram14]

Im going to jump out on a limb here and say that the gasket and or head over the coolanted cylinder is bad. If you look at the carbon build up on the piston to the left compared to that of the right it is pretty clear that coolant has been run through there for some time now. To the OP, there are some pictures floating around the forum of what cracked heads look like. Typically its the thin aluminum between the valves on the underside of the heads that crack. That being said, I am not sure if a cracked head would cause the coolant to run into the cylinder, but not having ever worked with that exact scenario I could be wrong.